Central granular cell odontogenic tumors (CGCOTs) are rare, benign, slowly growing odontogenic neoplasms. Due to their uncertain histogenesis, CGCOTs are still not included as a distinct entity in the WHO classification (2017) of odontogenic tumors. We report a case of CGCOT involving the right side of maxillary anterior region of a 39-year-old white female. Immunohistochemical staining showed that granular cells positively expressed CD68 and vimentin, and negatively expressed S-100 protein. Meanwhile, we searched PubMed, Google Scholar, and Scopus databases to summary the clinico-pathological features of 51 reported cases of CGCOT. The results showed that the granular cells of 28.6% cases were immunopositive for vimentin and CD68, and odontogenic epithelial cells were positive immunoreactivity for cytokeratin. These findings reinforced the mesenchymal origin of granular cells and the odontogenic nature of epithelium islands.
Humans ; Female ; Adult ; Vimentin ; Odontogenic Tumors/pathology* ; Epithelial Cells/pathology* ; Keratins

Objective: To investigate the clinicopathological characteristics of plurihormonal PIT1-lineage pituitary neuroendocrine tumors. Methods: Forty-eight plurihormonal PIT1-lineage tumors were collected between January 2018 and April 2022 from the pathological database of Sanbo Brain Hospital, Capital Medical University. The related clinical and imaging data were retrieved. H&E, immunohistochemical and special stains were performed. Results: Out of the 48 plurihormonal PIT1-lineage tumors included, 13 cases were mature PIT1-lineage tumors and 35 cases were immature PIT1-lineage tumors. There were some obvious clinicopathological differences between the two groups. Clinically, the mature plurihormonal PIT1-lineage tumor mostly had endocrine symptoms due to increased hormone production, while a small number of immature PIT1-lineage tumors had endocrine symptoms accompanied by low-level increased serum pituitary hormone; patients with the immature PIT1-lineage tumors were younger than the mature PIT1-lineage tumors; the immature PIT1-lineage tumors were larger in size and more likely invasive in imaging. Histopathologically, the mature PIT1-lineage tumors were composed of large eosinophilic cells with high proportion of growth hormone expression, while the immature PIT1-lineage tumors consisted of chromophobe cells with a relatively higher expression of prolactin; the mature PIT1-lineage tumors had consistently diffuse cytoplasmic positive staining for keratin, while the immature PIT1-lineage tumors had various expression for keratin; the immature PIT1-lineage tumors showed more mitotic figures and higher Ki-67 proliferation index; in addition, 25.0% (12/48) of PIT1-positive plurihormonal tumors showed abnormal positive staining for gonadotropin hormones. There was no significant difference in the progression-free survival between the two groups (P=0.648) by Kaplan-Meier analysis. Conclusions: Plurihormonal PIT1-lineage tumor belongs to a rare type of PIT1-lineage pituitary neuroendocrine tumors, most of which are of immature lineage. Clinically increased symptoms owing to pituitary hormone secretion, histopathologically increased number of eosinophilic tumor cells with high proportion of growth hormone expression, diffusely cytoplasmic keratin staining and low proliferative activity can help differentiate the mature plurihormonal PIT1-lineage tumors from the immature PIT1-lineage tumors. The immature PIT1-lineage tumors have more complicated clinicopathological characteristics.
Humans ; Neuroendocrine Tumors ; Pituitary Neoplasms/pathology* ; Pituitary Hormones ; Growth Hormone/metabolism* ; Keratins

Humans ; Keratins ; Immunohistochemistry ; Colorectal Neoplasms/pathology* ; Staining and Labeling ; Neoplasm Staging

Objective: To investigate the clinicopathological features, immunophenotype and differential diagnoses of SMARCA4-deificient undifferentiated carcinoma (SMARCA4-DUC) of the gastrointestinal tract. Methods: The clinicopathological data and immunohistochemical profiles of nine cases of SMARCA4-DUC of the gastrointestinal tract diagnosed in Fudan University Shanghai Cancer Center, from 2018 to 2021, were analyzed retrospectively. The relevant literature was reviewed. Results: There were seven males and two females with age at presentation ranging from 39 to 74 years (mean 58 years, median 64 years). The tumor occurred in the stomach (6 cases), right hemicolon (2 cases) and duodenum (1 case). The main symptoms included dysphagia, abdominal pain, diarrhea and melena. Five cases were resected, and the tumor sizes ranged from 5.0 to 8.7 cm (mean 6.7 cm). Microscopically, the tumor was composed of sheets of undifferentiated round to epithelioid cells with large vesicular nuclei harboring prominent nucleoli and displaying brisk mitotic activity. Foci of dyscohesive rhabdoid cells were also noted. The tumor cells were generally uniform; however, prominent pleomorphism and spindle cell component was present in one case each. Five cases contained areas of coagulative necrosis, and one case showed myxoid change of the stroma. By immunohistochemistry, eight cases showed complete loss of BRG1 (SMARCA4) and BRM (SMARCA2) expression. Whereas the expression of these two markers was lost in the epithelioid component of one case, it remained in the spindle cell component (mosaic pattern). Apart from one case with partial expression of pan-cytokeratin, all other eight cases showed either limited (<5%, n=5) or totally negative (n=3) staining of pan-cytokeratin. In addition, four cases also expressed CD34, SOX2 and SALL4. Six patients had follow-up data: four died of disease within 1 year. Conclusions: SMARCA4-DUC of the gastrointestinal tract represents a highly aggressive malignancy with poor outcome. Due to lack of cell-specific differentiation, it is not uncommonly misdiagnosed as a wide variety of poorly-differentiated or undifferentiated tumors. Increased recognition of this rare but distinctive entity not only facilitates the diagnosis and differential diagnosis, but also provides important therapeutic and prognostic information for the clinicians.
Biomarkers, Tumor/genetics* ; Carcinoma/pathology* ; China ; DNA Helicases ; Female ; Gastrointestinal Tract/pathology* ; Humans ; Keratins ; Male ; Nuclear Proteins ; Retrospective Studies ; Transcription Factors

Human hair, a kind of natural fiber mainly composed of keratin and keratin-associated proteins, is a good biological sample that can be used to characterize the status of the body in a certain period of time. It is of highly importance in the detection of drugs, alcohol and stimulants because of the advantages of low cost, easy collection, easy transportation and storage. Proteomics is an emerging technology widely used in the field of life sciences to study protein expression and regulation at the holistic level. Investigating the composition and dynamic changes of hair proteins in different populations would have great potential in finding disease markers and distinguishing personal traits. In this paper, the structure and composition of hair, the changes of hair composition under psychological stress, and the research progress of hair proteomics were comprehensively reviewed. This will help using hair proteomics to identify body characteristics.
Humans ; Human Characteristics ; Proteomics ; Hair/chemistry* ; Keratins/chemistry* ; Metabolomics

The incidence and mortality rates of gastrointestinal (GI) cancer remain high. Despite constant improvements in diagnostic and therapeutic techniques, the early diagnosis, mid- and late-stage treatment, drug tolerance, and cancer recurrence and metastasis in GI cancer remain challenging. In this review article we summarize the recent research advance in the roles of keratins in GI cancer, with the hope that they will become efficient biomarkers for the prediction, diagnosis, or treatment of these malignancies.
Biomarkers, Tumor ; Gastrointestinal Neoplasms/therapy* ; Humans ; Keratins

Primary malignant melanoma of the breast (PMMB) is a rare tumor with only a few case reports available in the literature. We report two cases of PMMB, one derived from the breast parenchyma and the other from the breast skin. The first case consisted of atypical epithelioid cells without overt melanocytic differentiation like melanin pigments. The tumor cells showed diffuse positivity for S100 protein, tyrosinase, and BRAF V600E. However, the tumor cells were negative for cytokeratin, epithelial membrane antigen, and HMB-45. The second case showed atypical melanocytic proliferation with heavy melanin pigmentation. The tumor cells were positive for S100 protein, HMB-45, tyrosinase, and BRAF V600E. These two cases represent two distinct presentations of PMMB in terms of skin involvement, melanin pigmentation, and HMB-45 positivity. Although PMMB is very rare, the possibility of this entity should be considered in malignant epithelioid neoplasms in the breast parenchyma.
Breast ; Epithelioid Cells ; Keratins ; Melanins ; Melanoma ; Monophenol Monooxygenase ; Mucin-1 ; Pigmentation ; Skin

We report a rare case of hilar squamous cell carcinoma. A 62-year-old Korean woman complaining of nausea was referred to our hospital. Her biliary computed tomography revealed a 28 mm-sized protruding solid mass in the proximal common bile duct. The patient underwent left hemihepatectomy with S1 segmentectomy and segmental excision of the common bile duct. Microscopically, the tumor was a moderately differentiated squamous cell carcinoma of the extrahepatic bile duct, without any component of adenocarcinoma or metaplastic portion in the biliary epithelium. Immunohistochemically, the tumor was positive for cytokeratin (CK) 5/6, CK19, p40, and p63. Squamous cell carcinoma of the extrahepatic bile duct is rare. To date, only 24 cases of biliary squamous cell carcinomas have been reported. Here, we provide a clinicopathologic review of previously reported extrahepatic bile duct squamous cell carcinomas.
Adenocarcinoma ; Bile Ducts, Extrahepatic ; Carcinoma, Squamous Cell ; Common Bile Duct ; Drug Therapy ; Epithelial Cells ; Epithelium ; Female ; Hepatic Duct, Common ; Humans ; Keratins ; Klatskin Tumor ; Mastectomy, Segmental ; Middle Aged ; Nausea

Thymus is an encapsulated organ having its bilateral origin from the third pharyngeal pouch. It appears to be a single organ but actually it is bilobed. It attains its maximum development at puberty and then it begins to involute. The parenchyma is replaced by adipocytes and lymphocyte production declines. Here we present a large thymus with a small area of persistent active tissue in it which was obtained during routine undergraduate dissection class. Tissues taken from different quadrants of the large thymic mass were processed, embedded in paraffin and sections were taken for hematoxylin and eosin staining which showed presence of thymic tissue in only one quadrant. Further sections from that quadrant was treated with cytokeratin to confirm its epithelial origin. Therefore knowledge of a large persistent thymus will be helpful to the radiologists and surgeons for making differential diagnosis and in avoiding unnecessary surgical intervention.
Adipocytes ; Adolescent ; Aged ; Cadaver ; Diagnosis, Differential ; Eosine Yellowish-(YS) ; Hematoxylin ; Humans ; Immunohistochemistry ; Keratins ; Lymphocytes ; Paraffin ; Puberty ; Surgeons ; Thymus Gland

A renal oncocytoma was diagnosed in an 8-year-old female Maltese dog with a history of renal cysts. Tumor cells were not detected until six months after observation of renal cysts. Nephrectomy was performed to treat the neoplasia. Tumor-like masses with numerous nodules were observed in the inner surface of cysts present in the caudal part of the left kidney. Histologically, the tumor consisted of cells with abundant eosinophilic cytoplasm. The diagnosis was based on histological features, periodic acid-Schiff reaction, and immunohistochemical cytokeratin staining. Based on a literature review, this is the first canine renal oncocytoma case reported in Korea.
Adenoma, Oxyphilic ; Animals ; Child ; Cytoplasm ; Diagnosis ; Dogs ; Eosinophils ; Female ; Humans ; Keratins ; Kidney ; Korea ; Nephrectomy ; Periodic Acid-Schiff Reaction